As informatization popularizes and structured and non-structured data explosively increase, more and more enterprises and people start to realize the importance of data protection and increase inputs and constructions. A data backup system that is formed by data backup software and a virtual tape library (Virtual Tape Liberary, VTL) device becomes a rather popular solution.
FIG. 1 is a data flow diagram of data backup performed based on data backup software and a VTL device according to the prior art. As shown in FIG. 1, the data backup software on a backup server packages data on client A and client B and backs up the packaged data to the VTL device through a VTL interface by using a virtual tape as a backup medium. FIG. 2 is a data flow diagram of data recovery performed based on data backup software and a VTL device according to the prior art. As shown in FIG. 2, when some data on a client is damaged or lost and data recovery needs to be performed, the data backup software on the data backup server recovers one or several virtual tapes in the VTL device to original client A and client B through the VTL interface according to a recovery policy, and then the data backup software unpacks a backup data packet in the virtual tape, so that client A and client B recover data to a state of a backup point.
When data recovery is performed by using the above method, no matter whether all data before a backup point is recovered or only a small amount of partial data or files is recovered, it needs to be implemented by using the data backup software manually, thereby increasing complexity of data recovery and reducing recovery efficiency; in addition, all recovery data flows need to pass through the backup server and occupy considerable resources of the backup server. If the backup server is performing a data backup task, it may increase the time for performing the data backup task and reduce the data recovery efficiency.